How did Romans manipulate numbers with their numeral system?

[rurallib]

you know - add, subtract, multiply and divide? For some reason this floated into my brain the other day and now it is kind of haunting me.

There must have some way they could do it - after all they built viaducts and coliseums and homes and buildings. So they must have been able to add etcetera.

But let's just do a simple multiplication to illustrate how difficult it must have been: 7 times 14 = 98 or in Roman numerals:
VII times XIV = XCVIII (I think I got that right).

Trying to do math in your head with Roman numerals can really give you a headache.

[Irish_Dem]

1. They used a portable abacus or counting boards.

If you have ever seen someone use one, it is a very rapid way to do complicated math.

[rurallib]

3. so they were actually using a base 10 system?

[Irish_Dem]

6. Yes, the abacus was a hand held calculator using a decimal (10 base) system.

Then they could translate that into the roman numeral system.

You might want to look it up, I only know the basics of it.

I am a US military kid and growing up in Japan saw the abacus in action there quite a bit.
Very rapid complicated calculations done in an instant.

It was from the ancient Romans, Greeks, Chinese.

[Ilsa]

5. Not too complicated. My fifth or sixth grade class

learned to use a simple one, but not a Chinese abacus.

[underpants]

2. Well...

[BootinUp]

7. such a useful meme. nt

[underpants]

10. I was being ironic and sarcastic but, yes, it is very useful

I’d seen that for years* but wasn’t aware of its racist element until my daughter explained it to me. The idea that Egyptian couldn’t POSSIBLY have designed the pyramids as well as other structures without the help of some external help implies that they just didn’t have the intelligence to do it. Egyptians look a lot different than Europeans, in this case Romans.

I don’t mean to suggest that Giorgio Tsoukalos is racist. He’s has a communications degree, worked in pro boxing promotions, and bought the time in The History Channel to put that on. The hair and the meme have propelled him into a career.

https://en.wikipedia.org/wiki/Giorgio_A._Tsoukalos

[surfered]

4. I didn't know it could be done.

[Abnredleg]

8. There are eleven types of people in the world

Those who understand Roman numerals, and those that don't.

[rurallib]

9. ...